Electromagnetic device



Patented Feb. 28, 1928.

UNITED STATES tetona PATENT OFFICE.

JOHN S. GARVIN, OF BOGOTA, NEEV JERSEY, ASSIGNOR TO WESTERN ELECTRIC COM- FA'NY, INCORPORATED, OF NEW YORK, N. Y., A CORPORATION OF NEW4 YORK.

ELECTROMAGNETIIIC DEVICE.

Application filed November 9, 1923.

This invoi'ition relates to electromagnetic devices, and particularly, to electromagnetic devices of the slow acting type.

In electrical systems the operation of various devices usually follows a predetermined sequence, and it is often necessary to insure that one electromagnetic device or relay has sufficient time to function before another operates its contacts. Accordingly,

0 various types of relays have been developed such as slow-to-operate, quick-to-release, o r quicloto-operate, slow-to-release, and it 1s with these types of relays that this invention is concerned. Various means for rctarding the action of such relays have been employed as, for example, the placing` of a copper sleeve about the core, or the use of various spring adjustingr devices all of which have proved more or less unsatisfactory as the required lag in operation is not easily controlled under conditions of varying operating currents.

The object of this invention is to produce a slow-to-actuate electromagnetic device which functions to provide a desired eon lstant time interval under varying current conditions.

This object is obtained in accordance with one feature of the invention by the provision of a relay having a plunger type core arranged to so control an armature that contact springs controlled thereby will not be actuated until the plunger is fully attracted, and by the provision of an escapement mechanism and a balance wheel to control the speed at which the plunger may be attracted. The use of this construction makes it possible to maintain constant the time interval between the energizing of the relay and the operation of the contacts under the varying current conditions are encountered in practice.

In the drawings,

F ig. 1 is a side elevation` of a slow-to-operate, quick-to-release relay with a portion of the frame work removed.

Fig. 2 is a top plan of the relay of Fig. 1 with the core, armature and contacts springs in normal position.

Fig. B is a top plan of tbc'rcluy of Fig. 1 with the core, armature and'contact springs in operated position.

Y Fig. 4 is a top plan of the movable parts of a quiclr-to-operate, slow-to-release relay.

Serial No. 673,682.

As shown in Fig. 1 the relay consists of a at one end to the support t provided with lugs 5 by means of which the relay may be secured to 'a mountingl plate. This tube 3 is surrounded by a coil winding' 6 held in place by means of insulating spool heads 7 and 8 mounted on each end of the tube 3. At the end of tube 3 adjacent to spool head 7 is secured a bracket 9 to which, in turn, is riveted a U-shaped mounting frame 10.` A core 11 of magnetic material is slidably mounted in the tube, being' supported at its inner end by the tube itself and at its outer end by a pin 12 projecting into a hole in the center of the coils to approximately the middle of the core, the outer core of the pin be ing secured to the portion 13 of the frame 10.

ll/lounted between the side portions 14 and 15 of frame 10 is the escapement mechanism operated by the core 11 which for this purpose is provided with a rack 16 engaging a pinion 17 mounted on shaft 18 secured between portions 14 and 15. Attached to one end ot' pinion 17 is the inner end of a spiral spring 19 the opposite end of which is secured to the frame portion 15 as shown at 50. Attached to the opposite end of pinion 17 is a disc 2O` to which is secured atV udiaofonally opposite points the pawl springs 21 engin.; crowned teeth 22 on an adjacent wheel 23. This wheel is mounted on shaft 18 and is provided with ratchet teeth 241 on its periphery .in position to be engaged'by an escapement pawl 25, secured to one end of a shaft At the opposite end of shaft 26 is secured a counter weight or balance wheel 27. The shaft 26 is mounted in bearings in portions 14 and 15. y

On opposite extensions of support 4 are mounted armature reeds 28, Contact springs 29, insulators 8O and plates 31 clamped to the extensions by means of screws 32 to form a unitary structure, with the contact springs 29 individually insulated from each otherl and; from the remainingF parts. The U-shapcd armature 38 comprises two parallel arms 84 riveted to the reeds 28` and a transverse portion 35 on which is mounted a roller 36 in proximity to one side of core 11. A `@groove 37 is provided in the side of the plunger 11 to cooperate with roller 36 is hereinafter described. Studs 38 of insulating` material are secured to the armature as shown to operate the contact springs 29 upon actuation of armature 33.

The operation ot the slow-to-operate7 quickie-release relay is as follows: rthe ilow of current tln'ough coil 6 draws core 11 into the tube 3 towards the center of the coil. 'llhe speed at which the core will travel is deterniined by the escapement mechanism and the balance wheel. The balance wheel nl Qi" controls the time oi oscillation o'l' the pawl 25, which in turn controls thc movement of the wheel 28, which is coupled to pinion 17 by means of pawls 21. rlfhc armature 33 which is sin'niltancously attracted by the cnergization ot the relay is, however, prevented from operating the spring contacts 29 until the core is fully attracted as until such time the roller 36 will ride on the side of the core. lWhen the core 11 is fully att() tracted the roller drops into the groove 3? whereupon the armature is permitted to move towards the center suiiiciently to operate contact spring 29. lt is thus seen that the lag in the operation olA Contact spring 29 depends upon the speed at which the core 11 is moved towards the center of the coil. This speed, being determined primarily by the size and weight ot' the various parts oit the escapement mechanism and counter weight. It will be understood that the proportions of these parts can readily be altered to suit various operating requirements. For example, by simply increasing the weight of the balance wheel 27 the speed oiZ the core will be materially reduced. lt is is also evident that by employing a core and escapement mechanism, such as shown, ordinary variations in the operating current will not materially afio tcct the operating time as the inertia of the parts tend to smooth out and equalize the effect of such variations. It may also be pointed out that the actual time consumed in closing the contacts after the roller has reached the edge of the groove is small as compared with the total time it takes the core to be attracted.` This is due to the sharp slope ot the walls of the groove which permits the roller to drop quickly into Vplace at the bottom of the groove.

At the deenergization o'l the relay, the contact springs will be released practically instantaneously by the return of the armature to normal under tension or the reeds te Q8. rlhe core will also be returned to normal by the energy stored up in the spiral spring 19 during the rotation of the pinion 17 at the attraction ot the core. rlhe core and pinion 17 only will return to normal as G0' the pawl 21 is so arranged that the escapement mechanism and counter weight are only coupled to move with and control the core during its movement from normal position.

@a It should be understood that this innastreeft vention is not coniined to slow-to-operate, quiclt-to-release relays, but may readily be applied to quick-to-operate, slowtorelease relays by merely placing the roller 3G on the opposite side oi the core 11, locating the groove 37 in the core 11 so that the roller normally rests therein and changes the cscapement mechanism to operate in the opposite direction so that it acts to retard the core duringl its return movement to normal position under the intluence o'il the energy stored in spring 19, instead of as shown in lfigs. 1 to 3 during the time it is attracted towards the center of the coil.

rlhis modified torni ot the invention is illustrated plainly in Fig. l. ln this case the energizing ot the winding attracts the armature 33 to operate the contact springs 29 instantaneously and moves the core against the tension ot spring 19 to its fully attracted position without operating the escapement mechanism. it the release, however, or core 11 the escapement mechanism is engaged and retards its return movement to normal. By this means the roller 3G by riding on the side of core 11 during its entire return movement holds the Contact spring 29 operated and only permits thc armature to be released when the roller 36 drops into groove 37 at the end of the return stroke.

What is claimed is:

1. An electromagnetic device comprising an energizing winding, a movable core and an armature designed to be attracted to said lse lil

core upon the energization otI said winding,

and means tor preventing the movement of the armature during a substantial period ot the movement of the core.

2. An electromagnetic device comprising an energizing winding, a movable core, an armature attracted to, and whose movement is controlled by the core, contact springs operated by the armature, and means for retarding the movement of the core.

3. An electromagnetic device comprising an energizing winding, a movable core, an armature adapted to be attracted to said core upon the energization of said winding, means for preventing the operation of the armature .until the core has been fully attracted, and means for retarding the movement of the core. Y v 1 el. ln combination, an electromagnetic device having a plunger type core, circuit con* trolling means, and means tor engaging said core upon the energization of said device and maintaining said circuitV controlling means inoperative for a predetermined period of time after the energization of said electromagnetic device.

5. ln combination, an electromagnetic de vice having a plunger type core, circuit controlling means, and means slidably engaging said core and adapted to maintain said circuit controlling means inoperative 'for a predetermined period of time after the energi zation ot' said electromagnetic device.

6. rr solenoid type electromagnet comprising` a plunger, an armature adapted to be attracted thereby and an escapement mechanism for retarding tlie movement ot tlie plunger in tlie solenoid.

7. A solenoid type electromaguet comprising a plunger, an armature controlled thereby and an escapement mechanism and a balance wheel 'for retarding the movement of the plunger and restraining the actuation of said armature during substantially the whole movement ot said plunger.

8. A solenoid type electroinagnet comprising a plunger, an armature adapted to be attracted t-liereloy, an escapement mechanism and a balance wheel for retarding the movement of the plunger, and contacts controlled by the armature.

9. A circuit controller comprising a winding, a core movable with respect to said winding, an escapement mechanism or controlling tlie movement of said core, a bal ance wlieel for controlling` tlie movement ot said escapemcnt mechanism, contacts 'for controlling an external circuit, an armature 'for controlling said contacts, and a roller associated with said armature and slidably eooperating with said core to control t-he movenient ot said armature.

l0, An electromagnetic circuit cont-roller comprising a winding, a core movable tliereinv1 and having a depression in one side thereoi", an cscapement mechanism t'or rctarding the movement ot tlie core, a balance wheel for tlie escapement mechanism, an arn'iature, contacts, and a roller carried by the armature and engaging the core to allow movement oit the armature to control engagement and disengagement oi tlie contacts upon registration and deregistration ot the roller and depression.

ll. An electromagnetic circuitcontroller comprising a winding, a core provided with a depression in one side thereof and movable in tlie winding, means to retard the movement of the core, an armature, contacts and a roller carried by tlie armature and engaging tlie core to control engagement and disengagement of the contacts upon registration and deregistration of the roller and depression. l

In witness whereof, I hereunto subscribe my name tliis 5 day of November A. D. 1923.

JOHN S. GARVIN. 

